The present invention relates generally to material chopping. To assist in providing a background of the invention problems associated with choppers used to produce stover are discussed. It is to be understood, however, that the present invention is not to be limited to this specific application.
Recently, increased interest has been placed on a stover. The term “stover” is generally the stalk and leaf materials of a crop without the harvested grain. Sometimes this is referred to as crop residue which is indicative of the relative value of stover compared to grain. However, it is now recognized that stover, a biomass material, can be used in ethanol production and thus has value beyond its traditional usage.
To use stover as a biomass material, it is desirable for the stover to be of a uniform length of cut. For this reason, improved chopper designs are needed. Two common chopper designs are the flail style chopper and the slicer/shear style chopper. The flail style chopper uses hammers attached a center drum to chop material. It relies on the impact of the hammer on the material to cut the material. The slicer/shear style chopper uses shear surfaces rotating on a center drum that pass near a bank of stationary knives to shear material. These types of chopper designs have major drawbacks. In particular, the flail style choppers do not provide a uniform length of cut and they require more power to operate than a shear style chopper. Slicer style choppers employ shear style cutting, but they do not have the ability to uniformly size material that is randomly oriented. Therefore, problems remain.
Therefore it is a primary object, feature, or advantage of the present invention to improve over the state of the art.
It is a further object, feature, or advantage of the present invention to provide a two axis crop residue chopper which may be used to cut crop residue for the purpose of harvesting biomass feed stock for conversion to ethanol or any other use.
It is a still further object, feature, or advantage of the present invention to provide a chopper that cuts crop residues on perpendicular planes.
Another object, feature, or advantage of the present invention is to provide more uniform cut length to chopped crop residue.
Yet another object, feature, or advantage of the present invention is to provide a chopper where the depth of cutting teeth control length of cut.
A further object, feature, or advantage of the present invention is to provide for cutting of material regardless of orientation of material at entrance to chopper.
Yet another object, feature, or advantage of the present invention is to allow for use of a knife and shear bar configuration to cut crop residue cleanly and with lower power requirements than alternative methods.
Another object, feature, or advantage of the present invention is to use stationary vertical knives between rotating shear knives to provide either standard impact cutting or shear cutting on the perpendicular plane.
Yet another object, feature, or advantage of the present invention is to provide chopped and sized crop residue suited for either crop residue harvest or for standard residue management practices.
It is another object, feature, or advantage of the present invention to reduce the power required to chop the stover.
Another object, feature, or advantage of the present invention is to increase stover density for transport by cutting stover into uniform, small particles.
One or more of these and/or other objects, features, or advantages of the present invention will become apparent from the specification and claims that follow. The present invention is not to be limited to or by these objects, feature or advantages.